Starters?

hello i just made a 2.5 liter yeast starter. Now my ? how many days does it take to ferment out so i can chilled it for a few day an decant it an pitch just the yeast

I use a stir plate for my starters and wait 24 hours typically but sometimes a bit longer depending on what time of day I started it and what I have going on the next day.

Agreed, depending on the size of the starter and age of the yeast (older yeast will take longer to get started) I usually let mine go for 24-48hrs on a stir plate. Then cold crash for another 24-48hrs. For 2.5L, I’d probably let it go for about 36hrs and then cold crash for a day or two. The cold crashing time also depends on the yeast. Some floc quicker.

Making your starter 4 days prior to brew day should usually give you plenty of time to ferment out then cold crash. 2 days would be enough for a smaller starter, say between 1 & 2L.

I usually wait 24 hours after visible fermentation is done, take it off stir plate, then crash for a couple days.